Hexachaetus kirschenhoferi, Tian, Mingyi & Deuve, Thierry, 2016

Tian, Mingyi & Deuve, Thierry, 2016, Re-definition and review of the Oriental genus Hexachaetus Chaudoir, 1871 (Coleoptera: Carabidae: Orthogoniini), Zootaxa 4169 (3), pp. 540-554 : 546-548

Hexachaetus kirschenhoferi n. sp.

( Figures 6 , 14–15 )

Diagnosis. Small sized for lateralis species group, body moderately elongate-ovate, smooth, polish, and impunctate; body yellow, head, longitudinal median portion of pronotum marginal areas central marking of elytra black, elytral black marking elongated anchoreaform, occupied at least intervals 1 and 2 in the narrowest portion; ligula 6-setose, clypeus bisetose, pronotum strongly convex, lateral expanded margin distinctly reflexed, hind angle round off, elytra strongly and obliquely truncate at apex, inner apical angle acute and sharp, striae rather deep, intervals convex, middle tibia slightly dilated in male.

Length: 11.0 mm; width: 4.5 mm. Habitus as in Fig. 6 .

Description. Lateral sides of pronotum and elytra, femora, side margin of ventral thoraces, abdominal ventrites yellowish; head, median portion of pronotum, elytral marking of median portion and lateral margins, aentennomeres 1-3, and legs (except femora) dark brown to black; labrum, palps antennomeres 4-11 brown; head and pronotum smooth, glabrous, elytra with tiny and irregular punctures on intervals; microsculpture engraved meshes isodiametric on head, pronotum and elytra.

Head stout, as long as wide, clypeus somewhat uneven at base, bisetose; eyes large and very prominent, frontal impressions well-marked, foveate, not reaching the level of fore supraorbital pores; frons rather flat, vertex convex; mandibles stout, apex moderately hooked; mentum and submentum each with a pair of setae, ligula slightly enlarged at apex, 6-setose, central one pair of setae longest, middle pair longer than outers; palps subcylindrical, maxillary palpomeres 3 and 4 subequal, with a few setae, very short and sparsely located; labial palpomere 2 slightly longer than 3, bisetose on inner margin; labrum nearly quadrate, front margin straight, 6-setose, surface smooth; clypeus bisetose. Antennae moderately long, extending at base of elytra, pubescent from antennomere 4, antennomeres 1–3 and base 4 dark brown, other lighter, laterally dilated on apical antennomere 4, with a distinct central carina from antennomere 4 to 10; antennomere 1–3 glabrous, antennomere 1 with a long seta at subapex, and additional shorter setae at apices of 1–3 antennomeres; antennomere 1 longer than 3.

Pronotum transverse, PW/PL=1.73, widest at about middle; disc markedly convex, smooth and glabrous, without striae, wrinkles or punctures; both front and basal margin bordered, fore and hind transversal impressions well-marked, median line distinct; lateral expanded margins narrow at apex, then gradually widened towards base, distinctly reflexed (but only slightly reflexed near base); front slightly emarginated at middle, base bisinuate, median portion slightly produced backwards; hind and front angles round off; basal foveae shallow and faint.

Elytra elongate-ovate, convex; EL/EW=1.56; nearly parallel-sided, widest at middle; black marking extending to base, lateral margins and apex of elytra, crossing at least intervals 1 and 2 at the narrowest portion; base well bordered, apex deeply and obliquely truncate, outer angles pointed, inner angles very sharp; striae rather deep, intervals convex, odd and even intervals subequal at middle; interval 3 with basal and subapical setiferous pores, basal one well-marked, close to stria 3, subapical one small, close to stria 2; middle pore absent.

Fore tibia slightly dilated at apex, apex slightly obliquely truncate, outer margin sub-serrate; middle tibia dilated in male; hind legs slender, apex only slightly enlarged, apical spurs long and sharp, tarsomere 1 nearly twice as long as 2; tarsomere 3 longer than 4 which is deeply bilobed; all tarsal claws pectinate.

Prosternal process unbordered at apex; abdominal ventrite VII of male small but deeply emarginate at middle.

Male genitalia ( Figs. 14–15 ): Median lobe of aedeagus short and stout, faintly expanded near base, dorsal open large, ventral margin gently sinuate, apex blunt in profile; in dorsal view, apical lamella very broad and short.

Female: Unknown.

Remarks. This species is easily separated by its small-sized body, narrowed front of pronotum and the elongated anchoreaform of elytra marking.

Etymology. The name of this new species is dedicated to E. Kirschenhofer (Perchtoldsdorf, Austria), a specialist of Carabidae .

Distribution. Indonesia ( Fig. 20 d).

Figures

FIGURE 20. Distribution of Hexachaetus species (square: angulatus species group; round: lateralis species group; star: laevissimus species group; heart: vietnamensis species group; triangle: mulan species group; a. H. lateralis lateralis; b. H. lateralis maindroni; c. H. maculatus; d. H. kirschenhoferi n. sp.; e. H. brunki n. sp.; f. H. laevissimus; g. H. vietnamensis n. sp.; h. H. prodigus; i. H. mulan n. sp.)

FIGURES 5 – 8. Habitus of Hexachaetus species (5. H. maculatus Tian & Deuve, male, the holotype; 6. H. kirschenhoferi n. sp., male, holotype (photo: E. Kirschhofer); 7. H. brunki n. sp., male holotype; 8. H. laevissimus Chaudoir, 1878, female. Scale bar: 5.0 mm)

FIGURES 12 – 19. Male genitalia of Hexachaetus species, right lateral view and dorsal view for apical lamella (12 – 13. H. maculatus Tian & Deuve; 14 – 15. H. kirschenhoferi n. sp.; 16 – 17. H. brunki n. sp.; 18 – 19. H. vietnamensis n. sp.)